Fire alarm devices such as audible horns (audible/visible or A/V), loudspeakers (speaker/visible or SN) and visible strobes (visible only or V/O), are referred to as “notification appliances.” Typically, a fire alarm control panel (FACP) drives these devices over one or more “notification appliance circuits” (NACs). The strobes are used, for example, as an alert for the hearing-impaired, or for those in a high noise environment.